H5 avian flu virus found in Canadian poultry

Jun 19, 2006 (CIDRAP News ) – An H5 avian influenza virus was found in a dead gosling in a backyard flock in eastern Canada late last week, but authorities said today there is "no evidence" that the virus is the deadly H5N1 strain.

Meanwhile, Hungary was culling poultry following the recent confirmation of the country's first H5N1 outbreak in domestic birds, according to Agence France-Presse (AFP).

In Canada, the Canadian Food Inspection Agency (CFIA) announced Jun 16 that a young goose on Prince Edward Island had tested positive for an H5 virus. The gosling was one of four birds that died in a flock of about 40, according to a Jun 18 Reuters report. Further testing was under way at the National Centre for Foreign Animal Disease in Winnipeg, Man., the CFIA said.

"There is no evidence to suggest that we are dealing with the H5N1 strain currently in Asia and other countries," the CFIA said in an update today. "That virus is marked by very high mortality in birds, which was not observed in this particular situation."

If the virus turned out to be the deadly Asian strain of H5N1, this would mark its first appearance in North America. But mild H5 viruses have been found in Canadian poultry before. About 58,000 poultry were culled near Chilliwack, British Columbia, last November to stop an outbreak of a low-pathogenic H5 virus.

The CFIA destroyed the Prince Edward Island flock of 35 to 40 ducks, geese, and chickens Jun 16, the Reuters report said. In addition, the CFIA said today it had quarantined a farm next to the affected one and was testing the birds there.

"There has been no evidence of AI [avian influenza] in the birds on this second premises, but there has been regular movement of people and possibly animals between the two premises," the agency said.

A CFIA veterinarian named Jim Clark suggested that the four dead birds on the affected farm might have died of something other than avian flu. "There's no direct evidence that the influenza virus was the cause of the problem in the four birds that died," Clark told Reuters.

H5 and H7 viruses can have either high or low pathogenicity. Low-pathogenic forms circulating in poultry can mutate into high-pathogenic strains.

If the Prince Edward Island virus is found to be highly pathogenic, all poultry within 3 kilometers of the affected farm will be culled, according to CFIA spokesman Marc Richard, as quoted by the Bloomberg news agency today.

Canada had a bout with a highly pathogenic H7N3 avian flu virus in southern British Columbia 2 years ago, the Bloomberg reported noted. Authorities destroyed 17 million poultry to stop that outbreak.

In Hungary, poultry culling was already under way when the European Union's avian flu reference laboratory in Weybridge, England, confirmed Jun 16 that the deadly H5N1 strain caused a disease outbreak on a farm in Kiskunmajsa, according to a Jun 16 AFP report.

The outbreak was Hungary's first in domestic birds, according to an online report today by the weekly newspaper The Budapest Times. The country reported H5N1 cases in wild swans in February.

Hungary reported the poultry outbreak to the World Organization for Animal Health (OIE) Jun 9, listing the virus as an H5. The disease killed about 800 geese and prompted the culling of 2,300 more, according to the OIE report.

The Budapest Times said the virus was found on several farms. "Authorities said all poultry within one kilometer of the outbreaks must be destroyed, meaning about half a million birds," the story said.

Hungarian Agriculture Minister Jozsef Graf said the government had allocated 11 million euros to compensate farmers affected by the outbreak, the newspaper reported. Graf also said Hungary had asked the European Union for 32 million euros in compensation for losses due to avian flu.

In other developments, China reported an avian flu outbreak on poultry farms in the northern province of Shanxi, according to an AFP story based on information from Xinhua. The story gave no details on the size of the outbreak.

The deadly strain of H5N1 has affected poultry in 34 countries since late 2003, according to the OIE. The organization published a chart today that listed the number of reported outbreaks by country. Vietnam led the list with 2,313 outbreaks, followed by Thailand (1,078), Indonesia (211), Turkey (176), Romania (168), Russia (121), China (80), Nigeria (69), Ukraine (23), Korea (19), and Cambodia (16).